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1.
Fumaria capreolata was taken into cell suspension culture. The culture yielded a biomass of about 12 g dry weight per liter of medium; the dried cells contained ca. 0.1% of alkaloids. Besides choline, the following ten known isoquinoline alkaloids were isolated from the cell extract in crystalline form: coptisine, dehydrocheilanthifoline; (+)-isoboldine; magnoflorine; N-methylcoclaurine; (+)-reticuline; (–)-pallidine; protopine; sanguinarine; (–)-scoulerine. This is the most diverse isoquinoline alkaloid spectrum thus far published for a cell suspension culture. 相似文献
2.
Glucose-6-phosphate dehydrogenase [D-glucose-6-phosphate: NADP oxidoreductase, EC. 1. 1. 1. 49] obtained from spores of Bacillus subtilis PCI 219 strain was partially purified by filtration on Sephadex G-200, ammonium sulfate fractionation and chromatography on DEAE-Sephadex A-25 (about 54-fold). The optimum pH for stability of this enzyme was about 6.3 and the optimum pH for the reaction about 8.3. The apparent Km values of the enzyme were 5.7 X 10(-4) M for glucose-6-phosphate and 2.4 X 10(-4) M for nicotinamide adenine dinucleotide phosphate (NADP). The isoelectric point was about pH 3.9. The enzyme activity was unaffected by the addition of Mg++ or Ca++. The inactive glucose-6-phosphate dehydrogenase obtained from the spores heated at 85 C for 30 min was not reactivated by the addition of ethylenediaminetetraacetic acid, dipicolinic acid or some salts unlike inactive glucose dehydrogenase. 相似文献
3.
M Kiso S Tanaka M Tanahashi Y Fujishima Y Ogawa A Hasegawa 《Carbohydrate research》1986,148(2):221-234
The diastereoisomeric, 4-O-phosphono-D-glucosamine derivatives named in the title have been synthesized, starting from benzyl 2-amino-2-deoxy-4,6-O-isopropylidene-beta-D-glucopyranoside and (3RS)-3-hydroxytetradecanoic acid. 相似文献
4.
Effects of hemolysis, hematocrit, RBC swelling, and flow rate on light scattering by blood in a 0.26 cm ID transparent tube 总被引:1,自引:0,他引:1
The intensity of light scattering by blood in a tube of diameter 0.26 cm was measured with an apparatus devised by us at different angles on an incident cross-sectional plane. Changes in angular distribution of light intensity associated with hemolysis, and changes in hematocrit (Ht), red blood cell (RBC) swelling, and flow rate were plotted on polar coordinates. The dyssymmetry index, defined as the ratio of the intensity of light at 45 degrees to that at 135 degrees, was used to characterize the shape of the diagrams of light scattering. The index decreased with Ht, flow rate, but increased with RBC swelling. It is concluded that light scattering by blood requires intactness of the RBC membrane. Even when the cell membrane is intact, light scattering is subject to changes with the flow rate of blood, presumably due to RBC aggregation. 相似文献
5.
Tadao Niijima Takashi Umeda Manabu Kuriyama Hiroyuki Ohmori Yohsuke Matsumura Tomoyasu Tsushima Toyoko Tanahashi Jun Yoshimoto Toshihiko Asahi Norimasa Ike Taiichiro Johsen Noritaka Ishido Naoki Mitsuhata Takeshi Uyama Hiroyoshi Tanaka Hideo Ueda Jisaburo Sakatoku Norio Yamamoto Kazuo Nagata Yukitoshi Fujita Masaaki Morioka Kazuo Kurokawa Susumu Kagawa Tomoyuki Ishibe Yasutoshi Himeno Toyofumi Ueda 《Cancer immunology, immunotherapy : CII》1989,30(2):81-85
Summary In order to examine its clinical efficacy, recombinant human interferon- (rIFN-) was instilled intravesically into 51 patients with superficial bladder cancer. Ten patients, who received intermittent intravesical instillation at a dose of (3–36) × 106 U rIFN- on days 1–3 every week, showed no response. Thirty-two patients received intravesical instillation at a dose of (3–36) × 106 U every day for 10–20 days. Eight patients showed partial response, indicating an efficacy rate of 25%. Nine patients received divided doses of 18 × 106 U twice a day every day for 10–20 days. Six patients showed partial response, indicating an efficacy rate of 67%. This value was significantly higher than that obtained by administering divided doses. The response to intravesical instillation therapy with rIFN- varies with treatment protocol. Frequent and longer exposure to rIFN- may induce better regression of superficial bladder cancer. Six incidences of side-effects were found in five cases (9.8%): pollakiuria in one, pain on micturition in two, fever in two, and eruption in one case. All of these side-effects were slight and reversible after drug withdrawal. Laboratory tests showed only a few changes with low severity. Thus, rIFN- is potentially a new drug for instillation therapy of superficial bladder cancer, in view of the absence of adverse effects. 相似文献
6.
ATP-Activated Nonselective Cation Current in NG108-15 Cells 总被引:5,自引:0,他引:5
Hiromi Kaiho Junko Kimura Isao Matsuoka Tadanori Kumasaka Hironori Nakanishi 《Journal of neurochemistry》1996,67(1):398-406
Abstract: ATP (1 mM) induced a biphasic increase in intracellular Ca2+ concentration ([Ca2+]i), i.e., an initial transient increase decayed to a level of sustained increase, in NG108-15 cells. The transient increase was inhibited by a phospholipase C inhibitor, 1-[6-[[17β-3-methoxyestra-1,3,5(10)-trien-17-yl]amino]hexyl]-1H-pyrrole-2,5-dione (U73122), whereas the sustained increase was abolished by removal of external Ca2+. We examined the mechanism of the ATP-elicited sustained [Ca2+]i increase using the fura-2 fluorescent method and the whole-cell patch clamp technique. ATP (1 mM) induced a membrane current with the reversal potential of 12.5 ± 0.8 mV (n = 10) in Tyrode external solution. The EC50 of ATP was ~0.75 mM. The permeability ratio of various cations carrying this current was Na+ (defined as 1) > Li+ (0.92 ± 0.01; n = 5) > K+ (0.89 ± 0.03; n = 6) > Rb+ (0.55 ± 0.02; n = 6) > Cs+ (0.51 ± 0.01; n = 5) > Ca2+ (0.22 ± 0.03; n = 3) > N-methyl-d -glucamine (0.13 ± 0.01; n = 5), suggesting that ATP activated a nonselective cation current. The ATP-induced current was larger at lower concentrations of external Mg2+. ATP analogues that induced the current were 2-methylthio-ATP (2MeSATP), benzoylbenzoic-ATP, adenosine 5′-thiotriphosphate (ATPγS), and adenosine 5′-O-(2-thiodiphosphate), but not adenosine, ADP, α,β-methylene-ATP (AMPCPP), β,γ-methylene-ATP (AMPPCP), or UTP. Concomitant with the current data, 2MeSATP and ATPγS, but not AMPCPP or AMPPCP, increased the sustained [Ca2+]i increase. We conclude that ATP activates a class of Ca2+-permeable nonselective cation channels via the P2z receptor in NG108-15 cells. 相似文献
7.
K Kajita K Yasuda N Yamakita T Murai M Matsuda H Morita A Mori M Murayama S Tanahashi M Sugiura 《Endocrinologia japonica》1991,38(2):121-129
In an attempt to investigate the clinical significance of anti-pituitary antibodies in patients with hypopituitarism, anti-pituitary antibody in plasma was examined in 10 such patients (7 cases of isolated ACTH deficiency, 1 of partial hypopituitarism, and 2 of Sheehan's syndrome), on two or three occasions with an interval of more than 6 months (longitudinal study). In a total of 16 relatives of these 4 patients (2 cases of Sheehan's syndrome, one in each of partial hypopituitarism and isolated ACTH deficiency) and one patient not involved in the longitudinal study, anti-pituitary antibodies were also examined (family study). Anti-pituitary antibodies reacting with rat pituitary cytoplasmic antigens (pituitary cell antibodies: PCA) and pituitary cell surface antibodies (PCSA) reacting with GH3 cells and/or AtT-20 cells were measured with indirect immunofluorescence. The longitudinal study revealed the disappearance of antibodies in 3 patients, 2 PCA positive and one both PCA and PCSA positive. In 3 patients, altered antibody titers or a newly appearing antibody were found during the follow-up period. In 4 patients, the pituitary antibodies were negative during the follow-up periods. Of 16 family members studied, positive PCA was found in 3 members (2 in the families of patients with PCA positive Sheehan's syndrome, and 1 in the family of the patients with PCA positive partial hypopituitarism). Positive PCSA was found in 4 members (one in each of families of patients with partial hypopituitarism and isolated ACTH deficiency and of two cases of Sheehan's syndrome), and weakly positive PCSA was found in one family member of a patients with PCA positive Sheehan's syndrome.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
H O Kanayama T Tamura S Ugai S Kagawa N Tanahashi T Yoshimura K Tanaka A Ichihara 《European journal of biochemistry》1992,206(2):567-578
It is known that two types of high-molecular-mass protease complexes are present in the cytosol of mammalian cells; a 20S latent multicatalytic proteinase named the proteasome, and a large proteolytic complex with an apparent sedimentation coefficient of 26S that catalyzes ATP-dependent breakdown of proteins conjugated with ubiquitin. In this work, we first demonstrated that a low concentration of SDS was required for activation of the latent proteasome, whereas the 26S complex degraded substrates for proteasomes in the absence of SDS. Moreover, the 26S complex was greatly stabilized in the presence of 2 mM ATP and 20% glycerol. Based on these characteristics, we next devised a novel procedure for purification of the 26S proteolytic complexes from human kidney. In this procedure, the proteolytic complexes were precipitated from cytoplasmic extracts by ultracentrifugation for 5 h at 105000 x g, and the large 26S complexes were clearly separated from the 20S proteasomes by molecular-sieve chromatography on a Biogel A-1.5 m column. The 26S enzyme was then purified to apparent homogeneity by successive chromatographies on hydroxyapatite and Q Sepharose, then by glycerol density-gradient centrifugation. Electrophoretic and immunochemical analyses showed that the purified human 26S complex consisted of multiple subunits of proteasomes with molecular masses of 21-31 kDa and 13-15 protein components ranging in molecular mass over 35-110 kDa, which were directly associated with the proteasome. The purified 26S proteolytic complex degraded 125I-labeled lysozyme-ubiquitin conjugates in an ATP-dependent manner. The 26S enzyme also showed high ATPase activity, which was copurified with the complex. Vanadate and hemin strongly inhibited not only ATP cleavage, but also ATP-dependent breakdown of ubiquitinligated proteins, suggesting that the 26S complex hydrolyzes ATP and ubiquitinated proteins by closely linked mechanisms. These findings indicate that the 26S complex consists of a proteasome with proteolytic function and multiple other components including an ATPase that regulates energy-dependent, ubiquitin-mediated protein degradation. 相似文献
9.
Release of Excitatory Amino Acids from Cultured Hippocampal Astrocytes Induced by a Hypoxic-Hypoglycemic Stimulation 总被引:2,自引:0,他引:2
Tadanori Ogata† Yoichi Nakamura Taiho Shibata† Kiyoshi Kataoka 《Journal of neurochemistry》1992,58(5):1957-1959
An excess release of excitatory amino acids (EAA) is an important factor for postischemic brain damage. In the present communication, we demonstrate that cultured hippocampal cells release EAA after hypoxic-hypoglycemic treatment. The amounts of EAA released from astrocytes were appreciably above those released from neurons. Furthermore, the amount of aspartate released from astrocytes was comparable to that of glutamate, although the endogenous content of aspartate was one-fifth that of glutamate. The endogenous content of aspartate in astrocytes increased even after hypoxic-hypoglycemic treatment. These results suggests that ischemic neuronal death is due, at least in part, to the excitotoxicity of aspartate and glutamate derived from surrounding astrocytes. 相似文献
10.
The effect of thrombospondin, a major glycoprotein in the platelet alpha-granule, on the erythrocyte aggregation rate was investigated. Venous blood was sampled from 8 healthy male volunteers and anticogulated with 1.1 mg/ml EDTA(K2). The erythrocyte aggregation rate of each blood sample was measured with a whole-blood erythrocyte aggregometer before and after incubation with murine monoclonal antibody against human platelet thrombospondin. After 15 min incubation, the erythrocyte aggregation rate exhibited a significant decrease to 0.055 +/- 0.022/s, representing 71.9 +/- 8.7% of the control value (0.075 +/- 0.028/s) (p less than 0.0005). The results obtained suggest that thrombospondin may participate in the control of erythrocyte aggregability in the circulating blood. 相似文献